Nowadays, integrated chips are developed with the development of semiconductor technology. Integrated chip combines multiple chips into a single one, which enables an electronic product to accomplish more functions with smaller size. For example, a conventional baseband chip in a communication device has integrated different functions of multiple peripheral chips, which makes the communication device have a thin and compact appearance.
A typical application of integrated chip is to integrate a Bluetooth chip into a baseband chip. Thus, the communication device can accomplish functions of both baseband and Bluetooth without an additional Bluetooth chip, which saves cost for the communication device. The Bluetooth chip integrated into the baseband chip can communicate for data interaction with a Bluetooth host through a Host Control Interface (HCI), which is specified in Bluetooth protocol, such as a Universal Asynchronous Receiver/Transmitter (UART) interface or a Universal Serial Bus (USB) interface, or through a shared memory. No matter which type of data interaction is selected, the Bluetooth chip integrated into the baseband chip needs to be tested by a dedicated test equipment of the Bluetooth Qualify Body (BQB). If the Bluetooth chip is not integrated into the baseband chip, the test is performed by connecting, directly or indirectly, the Bluetooth chip with the test equipment via a particular data lead on the Bluetooth chip. This test method is simple and easy to be achieved. However, if the existing method is also used to test the Bluetooth chip integrated into the baseband chip, the baseband chip has to reserve two data leads dedicated for connecting a test equipment with the Bluetooth chip. However, the reserved data leads are unused when the communication device is in a normal operation mode. Accordingly, the conventional test method may cause a huge waste of lead resources which are very precious for baseband chips.
More information about related techniques may refer to U.S. Pat. No. 7,208,968B2.